Substrate processing systems have long been employed to process substrates to produce electronic devices (such as integrated circuit dies or flat display panels or solar panels). In a modern substrate processing system, multiple process modules (Mk) may be provisioned per system. This is commonly known as the clustered tool approach, and a cluster tool is commonly understood to include multiple processing modules for processing multiple substrates in parallel.
Generally speaking, each process module is configured to process one or more substrates in accordance with the same or different recipes/processes. Since the processing of substrates typically requires a plurality of process gases (such as etching or deposition or tuning gases), each process module (or chamber, as the term “chamber” is used interchangeably with “process module” herein) is typically provisioned with its own gas panel in the past in order to selectively provide a set of required process gases to the process module to execute a desired recipe.
To elaborate, a gas panel represents the arrangement that performs the function of receiving the plurality of process gases, selectively providing selective gases of the plurality of process gases to the process module in accordance with parameters specified by the recipe. These parameters may include one or more of volume, pressure, and temperature, for example.
Gas panels are, however, fairly bulky and are relatively expensive items to purchase, operate, and maintain. A typical gas panel includes a plurality of input and output gas lines, a plurality of valves for volume/pressure control and for safety/isolation of the individual process gases and associated sensor/control/communication electronics. The typical gas panel also typically includes a mixing manifold for mixing the process gases prior to supplying such process gases to the process module. The large number of components increases the cost to acquire, operate, and maintain the substrate processing system.
Furthermore, some plasma processing chambers, such as dielectric etch chambers, require multiple gas feeds to different regions or zones of the chamber. In an example dielectric etch tool that employs dual zone gas feeds, the recipe may specify that 60% of the process gas be directed to the center zone and 40% of the process gas be directed to the edge zone. A subsequent recipe in the same chamber may specify that 72% of the process gas be directed to the center zone and 28% of the process gas be directed to the edge zone. A commercially viable dielectric etcher that employs multi-zone gas feed needs to accurately accommodate a range of ratios for the various zones as specified by different recipes.
Reducing the cost of acquiring, operating, and maintaining substrate processing systems by simplifying and/or reducing the number of gas panels while still efficiently accommodating the multi-zone gas feed requirement for individual chambers